217055977829 has 4 divisors (see below), whose sum is σ = 219671110176. Its totient is φ = 214440845484.

The previous prime is 217055977819. The next prime is 217055977889. The reversal of 217055977829 is 928779550712.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 217055977829 - 2⁸ = 217055977573 is a prime.

It is a super-2 number, since 2×217055977829² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217055977819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1307566049 + ... + 1307566214.

It is an arithmetic number, because the mean of its divisors is an integer number (54917777544).

Almost surely, 2^217055977829 is an apocalyptic number.

It is an amenable number.

217055977829 is a deficient number, since it is larger than the sum of its proper divisors (2615132347).

217055977829 is an equidigital number, since it uses as much as digits as its factorization.

217055977829 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2615132346.

The product of its (nonzero) digits is 22226400, while the sum is 62.

The spelling of 217055977829 in words is "two hundred seventeen billion, fifty-five million, nine hundred seventy-seven thousand, eight hundred twenty-nine".